Claude Haiku 5.5
The final model of the Claude 5.5 wave and Anthropic's cheapest, fastest, most capable small model, built for high-volume, latency-sensitive work such as classification, extraction, routing, and computer use
Claude Haiku 5.5
Anthropic • October 2026
Training Data
Up to June 2026
Claude Haiku 5.5
October 2026
Parameters
Not disclosed
Training Method
Advanced Constitutional AI with adaptive thinking (medium effort by default, adjustable from low to max)
Context Window
1,000,000 tokens
Knowledge Cutoff
June 2026
Key Features
~90% Cheaper Than Haiku 4.5 • Up to 2.5× Faster per Agent Turn • 1M Context / 128K Output
Capabilities
Computer Use: Outstanding (72.4% OSWorld 2.1)
Speed: Outstanding
Cost Efficiency: Outstanding ($0.10/$0.50 per 1M tokens)
What's New in This Version
Beats Haiku 4.5 on nearly every benchmark at roughly a tenth of the cost: $0.10/$0.50 per 1M tokens, 30% lower task latency, and up to 2.5× faster inference per agent turn. It moves from 200K to 1M context, adds adaptive thinking with adjustable effort, and scores 45.9% on Humanity's Last Exam without tools (57.4% with tools)
The final model of the Claude 5.5 wave and Anthropic's cheapest, fastest, most capable small model, built for high-volume, latency-sensitive work such as classification, extraction, routing, and computer use
What's New in This Version
Beats Haiku 4.5 on nearly every benchmark at roughly a tenth of the cost: $0.10/$0.50 per 1M tokens, 30% lower task latency, and up to 2.5× faster inference per agent turn. It moves from 200K to 1M context, adds adaptive thinking with adjustable effort, and scores 45.9% on Humanity's Last Exam without tools (57.4% with tools)
Technical Specifications
Key Features
Capabilities
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